If you want to use global functions and variable dynamically you can use:

window[functionName](window[varName]);

Is it possible to do the same thing for variables in the local scope?

This code works correctly but currently uses eval and I'm trying to think of how else to do it.

var test = function(){

    //this = window

    var a, b, c; //private variables



    var prop = function(name, def){

        //this = window

        eval(name+ ' = ' + (def.toSource() || undefined) + ';');    



        return function(value){

            //this = test object

            if ( !value) {

                return eval('(' + name + ')');

            }

            eval(name + ' = value;')

            return this;

        };



    };



    return {

        a:prop('a', 1),

        b:prop('b', 2),

        c:prop('c', 3),

        d:function(){

            //to show that they are accessible via to methods

            return [a,b,c];

        }

    };

}();



>>>test

Object

>>>test.prop

undefined

>>>test.a

function()

>>>test.a()

1 //returns the default

>>>test.a(123)

Object //returns the object

>>>test.a()

123 //returns the changed private variable

>>>test.d()

[123,2,3]